[Tarantool-patches] [PATCH] build: fix linker flags for executable on MacOS

[Sergey Kaplun]

Hi, Igor!

Thanks for the patch!
LGTM, except a few nits below.

On 28.04.21, Igor Munkin wrote:
> This patch fixes inaccuracy in Tarantool build configuration introduced
> by commit 07c83aab5c066ca75c149112b331b4dbb81b3f38 ('build: adjust
> LuaJIT build system'). All those MacOS-related tweaks for __PAGEZERO
> size and preferred load address for the bundle are necessary only for
> builds with 32-bit GC area on 64-bit host. The only case fitting these
> conditions is x86_64 with no LUAJIT_ENABLE_GC64. All other 64-bit builds
> use 64-bit GC area unconditionally.
> 
> Part of #5983
> Needed for #5629
> Follows up #4862
> 
> Signed-off-by: Igor Munkin <imun at tarantool.org>
> ---
> 
> This patch partially fixes the build on M1. I tested it on tntmac07
> alongside with the changes Nikita made for libcoro[1]. As a result
> Tarantool has been successfully built, but fails to start. CI looks to
> be OK[2] except the known problems with ASAN[3].
> 
> Issue: https://github.com/tarantool/tarantool/issues/5983
> Branch: https://github.com/tarantool/tarantool/tree/imun/gh-5983-fix-build-on-m1
> 
> [1]: https://github.com/tarantool/tarantool/commit/309ce38
> [2]: https://github.com/tarantool/tarantool/commit/5465d7b
> [3]: https://github.com/tarantool/tarantool/issues/6031
> 
> 
>  cmake/luajit.cmake | 20 +++++++++++++++-----

Should we add corresponding ChangeLog entry?

>  1 file changed, 15 insertions(+), 5 deletions(-)
> 
> diff --git a/cmake/luajit.cmake b/cmake/luajit.cmake
> index 3d37164e8..9390d0dfd 100644
> --- a/cmake/luajit.cmake
> +++ b/cmake/luajit.cmake
> @@ -73,11 +73,21 @@ if(ENABLE_ASAN)
>      add_definitions(-DLUAJIT_USE_ASAN=1)
>  endif()
>  
> -if(TARGET_OS_DARWIN)
> -    # Necessary to make LuaJIT (and Tarantool) work on Darwin, see
> -    # http://luajit.org/install.html.
> -    set(CMAKE_EXE_LINKER_FLAGS
> -        "${CMAKE_EXE_LINKER_FLAGS} -pagezero_size 10000 -image_base 100000000")
> +if(TARGET_OS_DARWIN AND NOT LUAJIT_ENABLE_GC64)
> +    # XXX: This is not the best idea to build LuaJIT on MacOS
> +    # with GC64 disabled. But nobody will stop you from this.
> +    # You are warned. For more info see the following issue.

Typo: s/For more info/For more info,/

> +    # https://github.com/tarantool/tarantool/issues/2643
> +    message(WARNING "LUAJIT_ENABLE_GC64 is disabled for MacOS. "
> +                    "See #2643, why this is not a good idea.")

Nit: may be the full link is better here (like we do for coredumps).
Feel free to ignore.

> +    # XXX: Necessary to make LuaJIT (and hence Tarantool) work on
> +    # Darwin/x86_64, see the following links for more info:
> +    # * http://luajit.org/install.html#embed
> +    # * https://github.com/tarantool/luajit/blob/789820a/cmake/SetTargetFlags.cmake
> +    if(CMAKE_SYSTEM_PROCESSOR STREQUAL "x86_64")
> +        set(CMAKE_EXE_LINKER_FLAGS
> +            "${CMAKE_EXE_LINKER_FLAGS} -pagezero_size 10000 -image_base 100000000")
> +    endif()
>  endif()
>  
>  # Define the locations for LuaJIT sources and artefacts.
> -- 
> 2.25.0
> 

-- 
Best regards,
Sergey Kaplun